Prosecutors Allege Nicholas Knight Is the Leader of an Antigovernment Hacking Group

WASHINGTON—A Navy systems administrator assigned to the nuclear reactor department of an aircraft carrier was also the leader of an antigovernment hacking group, prosecutors alleged Monday.

Prosecutors say 27-year-old Nicholas Knight, an alleged hacker since age 16, led Team Digi7al, a group that broke into networks belonging to more than 30 governments, companies and individuals throughout 2012 and stole personal information about...